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Discovery of a large deletion of KAL1 in 2 deaf brothers
Sandrine Marlin1, Sandra Chantot-Bastaraud, Albert David
1*Centre de référence des surdités génétiques, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris; †Service de Génétique médicale, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris; ‡INSERM UMRS1120; §Département de génétique et d'embryologie médicales, INSERM U933, Hôpital Armand Trousseau, Assistance Publique Hôpitaux de Paris, Paris; ∥Département de génétique clinique, CHU de Nantes; ¶Service d'ORL pédiatrique, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris; #Laboratoire de Génétique moléculaire, Hôpital Necker-Enfants Malades, Assistance Publique Hôpitaux de Paris; **Institut de la Vision; ††UPMC, Université Pierre et Marie Curie, Paris 6; and ‡‡Laboratoire de biochimie et biologie moléculaire, Hôpital Trousseau, Assistance Publique Hôpitaux de Paris, Paris, France.
Objectives:
Kallmann syndrome (KS) usually combines an anosmia and a hypogonadotrophic hypogonadism. Hearing impairment was described in a few cases of KS. Our objective is to describe an unusual presentation of KS in 2 cases and to explore the pattern of inheritance in this family.
Patients:
Two brothers presented with a sensorineural hearing impairment associated with cryptorchidism and abnormal movements.
Results:
Genome-wide array analysis identified a large deletion of KAL1 in both patients confirming the diagnosis of Kallmann syndrome. The absence of familial history has been explained by a somatic mosaicism identified in their mother.
Conclusion:
The description of a hearing defect in 2 brothers with Kallmann syndrome allows asserting that deafness is part of the clinical features of this disease and must lead the physician to monitor the hearing function of Kallmann patients.
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